As is well known, a baby bottle is a tool to help infants or young children get formula needed for growth through bottle feeding instead of breast feeding. Typically the baby bottle is composed of a body part for containing infant formula, a nipple with a tap, and a coupling means for coupling the body part and the nipple to each other.
The body part is made of a transparent plastic material (i.e., synthetic resin) which is inexpensive, lightweight, and durable. The nipple is made of a soft material so that a baby can suck the infant formula via the nipple. The coupling means is coupled to the outside surface of an upper portion of the body part generally in a screw manner in order to seal the nipple to the body part.
Since germs easily stick to the baby bottle and bacteria multiply fast on the surface of the baby bottle once the baby bottle is used, the baby bottle is boiled to be sterilized so that babies will not be infected.
When sterilizing the baby bottle made of a plastic material in a boiling water, environmental hormones hazardous to babies' health are generated. The environmental hormones are transferred to baby's bodies along with the formula in the bottle, having a negative impact on the babies. The environmental hormones are also likely to be generated when hot water is poured into a synthetic resin bottle to prepare infant formula.
Meanwhile, a baby bottle made of glass is disadvantageous in that it is heavy, is not good for baby's emotional development due to its hardness, and it easily breaks even when it is made of tempered glass or heat-resistant glass.
In order to prevent hazardous environmental hormones from being generated from baby bottles, silicone-based baby bottles are proposed, such as a “silicone baby bottle” disclosed in Korean Patent Registration No. 0621163. That is, baby bottles made of silicone are increasingly being marketed. Silicone is comparatively expensive but it is highly resistant to heat and does not generate environmental hormones. For this reason, the demand for silicone baby bottles is increasing.
The baby bottle is provided with an air inlet, through which external air in a volume corresponding to the volume of formula fed to a baby is introduced in order to maintain a constant internal pressure. In conventional baby bottles, the air inlet is exposed to the outside.
When a baby is fed from the baby bottle, the tap is put into baby's mouth and the baby bottle is disposed upside down so that the formula in the baby bottle can flow into the baby's mouth. In this instance, since the air inlet is formed in the nipple and exposed directly to the outside, when the baby incidentally pauses sucking the formula during feeding, the formula in the baby bottle is usually discharged outside by backflow through the air inlet due to the increased pressure of the infant formula in the nipple. This discharged formula flows along the surface of the baby bottle and drops onto the baby's face, surprising or displeasing the baby. This discharged formula is easily exposed to germs and the baby is likely to be infected by the germs by accidentally consuming the formula on the surface of the baby bottle.
Accordingly, it is necessary to minimize the outflow of the formula through the air inlet when the baby pauses sucking the formula in the baby bottle during feeding and to prevent the formula from flowing along the surface of the baby bottle and dropping to the baby's face or mouth even when the backflow of the formula occurs.
It is also necessary to provide components of the baby bottle, i.e. body part, nipple and coupling means, as separate members in order for easy removal of foreign substances sticking to the baby bottle, and easy cleaning and boiling for disinfection. Furthermore, it is preferable that the components can be easily reassembled after being disassembled for cleaning and can be tightly sealed without allowing a gap between the components so that the formula will not leak through the gap after being reassembled.
Furthermore, since silicone is soft and easily deformable by external force, it is difficult to tightly reassemble the components of the baby bottle and thus unintended gaps may occur between the components after being reassembled.
Especially in the case of a baby bottle such as the “silicone baby bottle” disclosed in Korean Patent Registration No. 0621163 in which a coupler as the coupling means simply couples to the outer circumference of an opening of a body part of the bottle made of silicone in an inserted manner and a tap cover as the coupling means couples to the coupler in a screw manner, the opening of the body part of the baby bottle is simply inserted into the coupler and there are no other means to tightly couple the coupler and the body part to each other. Accordingly, when the coupler and the cover are screwed together or unscrewed from each other, the coupler and the body part are not tightly fitted to each other. That is, in even a state in which the opening portion of the body part is inserted into the coupler, the body part can be rotated. This hinders not only tight coupling between the coupler when assembling the baby bottle but also separation of the coupler and the body part when disassembling the baby bottle.
Furthermore, when assembling a baby bottle, a user holds a body part with one hand and rotates a cover with other hand in order to couple the body part and the cover in a screw manner. At this time, the body part is deformed by external force applied from user's hand and the cover is coupled to the body part in the deformed state. Accordingly, there is a possibility that a gap may occur in the contact site of the body part and the cover.
Furthermore, since silicone is soft, when the body part is pressed by user's hand, the cover or the coupler screwed with the body part is likely to be easily separated from the body part.
If this happens during feeding, the safety of the infant or young child cannot be secured.
Accordingly, when the baby bottle is made of silicone, the body part and the nipple need to be easily and simply coupled and decoupled by the coupling means, while ensuring secure coupling without allowing a gap between the body part and nipple when the body part and the nipple are coupled to each other. However, the conventional silicone baby bottle is not provided with such a coupling means.